1. Technical Field
This invention generally relates to electronic systems, and more specifically relates to analog-to-digital conversion.
2. Background Art
Modem life is becoming more dependent upon electronic systems. Electronics devices have evolved into extremely sophisticated devices, and may be found in many different applications. As electronics become more integrated into daily life, their reliability and accuracy becomes a greater and greater necessity.
One particular type of electronic component in which reliability and accuracy are of increasing importance is in analog-to-digital converters (ADC). ADCs are devices that receive an analog signal, and convert the received analog signal into a digital value that is in some way proportional to the analog signals. As digital computing devices have become more and more common, the need for accurate and reliable ADC devices is increasing.
Presently available ADC devices rely on complex circuitry and may not be robust enough or accurate enough for demanding applications. For example, in applications used in space craft, it is difficult to find ADC devices that have enough precision while also being radiation hardened for use in space.
Thus, what is needed is an improved apparatus and method for converting analog signals to digital signals that can meet the high reliability and precision requirements of modem systems.
The present invention provides a method and apparatus for analog-to-digital conversion that uses pulse width modulation to provide accurate and reliable conversion of analog signals. The methods and apparatus can be implemented in an analog-to-digital converter (ADC) that can meet the requirements of the most demanding environments. Additionally, the ADC can be implemented to provide the high precision needed for many applications.
The method and apparatus provides an ADC that converts a received analog input into a pulse width modulated signal with a duty cycle that is responsive to the analog input. The pulse width modulated signal is passed to a duty cycle mechanism that determines the duty cycle of the pulse width modulated signal. The determined duty cycle can then be used to generate a digital value that is proportional to the analog input. The preferred method and apparatus thus provide a reliable and accurate ADC that can be used in a wide range of environments.